A coupling member of this kind is described in DE 20 2009 013 140 U1.
Since the applicant of this utility model commercialized so-called fully automatic coupling members which are based on DE 102 38 895 A1, the fully automatic coupling members enjoy increasing popularity in the market place. The particular advantage of fully automatic coupling members lies in the fact that, when loading a container, for example, on a sea-bound ship, they automatically lock and again in contrast to semiautomatic designs, automatically unlock during unloading of the container. Thus, even when unloading the container, no manual unlocking of the coupling member by stowage personal is required any longer. Accordingly these fully automatic coupling members are able to securely connect two containers stacked above each other during a voyage.
Furthermore empty containers are often loaded and unloaded above each other in “tandem” which is also called “vertical tandem lift (VTL)”. Two containers stacked above each other, which are connected to each other with coupling members, are thereby simultaneously loaded or unloaded by raising the upper container. This is naturally not possible with fully automatic coupling members.
There is thus a need for coupling members which can be used both semi-automatically as well as automatically and, when needed, can be switched between the two methods of functioning. The term ‘semiautomatic’ is understood to mean that the coupling members lock independently (automatically) during loading of the container; during debarkation (unloading), on the other hand however, must be manually unlocked by stowage personal. Then whenever no loading or unloading in “tandem lift” is desired or a comparatively quiet sea journey is expected, these coupling members should be used in the fully automatic function. If, however, a loading and unloading in “tandem lift” is desired or rough seas are expected during the transit, these coupling members should be used in the semiautomatic function.
Coupling members are described in EP 2 007 656 B1 or EP 2 233 408 A1 which can switch between a fully automatic function and a fully manual function. These coupling members are usually in the full automatic mode when loading and unloading containers. If the upper container is displaced from the lower container, the coupling members can be switched to the second position completely manually, in which position no fully automatic unlocking is possible anymore. Now two empty containers stacked above each other can be loaded or unloaded in a tandem lift. In addition, after loading of the containers the coupling members can be brought in this manner into a so-called safe position. For that reason the coupling members must be manually switched by stowage personnel both when loading and unloading. These coupling members thus can only be switched between a fully manual position and a fully automatic position and therefore cannot meet the previously stated requirements.
The coupling member according to DE 20 2009 013 140 U1 named at the outset should satisfy the above stated requirements, thus should namely be switchable between a semiautomatic position and a fully automatic position. To that end the coupling member has a blocking element which in the semiautomatic position prevents the lower coupling projection from sliding out of the upper long hole in the corner fitting of the lower container. This blocking member must also be manually unlocked, so that the upper container can be loosened from the lower container.
The blocking member of the coupling member is pre-tensioned in the direction toward the automatic position and can be switched by means of a Bowden cable into a second position in which the coupling member is supposed to act as a semiautomatic coupling member, namely to facilitate an automatic locking with the container, but can only be manually unlocked. Upon a closer inspection of the document it turns out, however, that this coupling member too can only be switched between an automatic position and a completely manual position, since the blocking member is positively secured in the second position against displacement in the direction toward the automatic position.